A 10 point raise in blood sugar level as measured in mg/dl the (US), and not mmol/L (A1C and the rest of the world), is just as likely to be variance in the meter as it is in the actual blood sugar level. A 10 point raise in mmol/L would be very unlikely and mean certain hospitalization or death. 10 points variance in mg/dl is normal in healthy people, I wouldn't think much of it.